Uh oh: We're back to pre-recession debt levels

America's outstanding credit card debt is projected to total $900 billion by the end of the year, bringing the average indebted household's balance to $7,813—the highest amount since 2008, when the average was $8,428, according to a new analysis by credit card comparison website Card Hub.

"With seven of the past 10 quarters reflecting year-over-year regression in consumer performance, evidence is mounting to support the notion that credit card users are reverting to pre-downturn bad habits," wrote CardHub CEO Odysseas Papadimitriou in the report.

Rising debt levels come at a time when Americans have more access to their credit reports and better credit scores.

The national average FICO score is now 695—the highest it's been for at least a decade, according to the latest analysis from Fair Isaac Corp., which created the score. A separate analysis by Experian put the average VantageScore, which was developed by Experian and the other national credit reporting companies Equifax and TransUnion, at 667, which is still considered good. (Both scores range from 301 to 850.)

You can get free credit scores from websites such as Quizzle, Credit.com and Credit Karma, which may draw on your credit information from one or more of the three major credit bureaus and offer resources to help you improve your score. Some credit card issuers, including American Express (NYSE: AXP), Bank of America (NYSE: BAC), Chase (NYSE: JPM), Citi (NYSE: C) and Discover (NYSE: DFS), now provide customers with access to their FICO credit score for free too.

Yet major misunderstandings about credit cards persist. A new survey by Bankrate.com found 77 percent of Americans don't know that accounts with high outstanding balances hurt their credit scores, even if they pay the bills on time, and 55 percent said that carrying a balance can improve their credit scores.

"I was surprised that these misconceptions exist because credit scores and credit reports are now widely available," said Jeanine Skowronski, a credit card analyst at Bankrate.

Skowronski recommends that consumers look beyond their scores and "dive deep" into their credit reports to see how their behavior affects their scores.

Most credit reports will outline the risk factors you face and how to improve your score. Lenders usually give those with scores of 740 or higher the best rates.

As a group, millennials have been particularly hurt by their lack of credit card knowledge. While the average score is up overall, more than half of millennials, people age 18 to 34, reported FICO scores below 670, according to a recent NerdWallet analysis.

Good credit card management boils down to making payments on time, keeping balances low and having a portfolio of cards with good rates, Bankrate's Skowronski said.

"It's easy to say that you're going to throw all of your extra money toward debt payments," said Katie Brewer, a certified financial planner in Rowlett, Texas, who works with millennials. "But it's smarter to focus on increasing emergency savings, receiving the employer match in a 401(k) plan and investing while paying down debt."